this is "nightline." >> tonight as twisters tear through america's heartland we take yo to ground zero. we're with some of the best storm chasers in the business. ch why they do it and the cutting edge technology they news to cap capture these pictures. and how you can stay safe in a storm like this. and how to marry harry. he's totally single and here in the states tonight. we go inside our real life princess class for a hopeful single women. and this is why harry is really here tonight. the invictus games.

wounded warriors competing and overcoming massive odds. we're right there with one father overcoming devastating injuries to inspire his own son. first, the night line five. >> if your family outing is magical for the wrong reasons, you may be mutting through allergies, try zyrtec. muddle no more. >> i smoked a lot and quit a lot, but ended up nowhere. now i use this. >> the nicoderm cq patch helps prevent the urge to smoke all day. >> i want this time to be my last time. that's why i choose

good evening. as we come on the air millions of americans are on alert for

tornadoes. massive monster twisters have been going across the plains causing extensive damage and tonight we are out with the storm chasers. how do they stay safe and how can you? abc reporting from oklahoma. >> reporter: tonight, heartache in the heartland as a series of twisters touch down hours ago. a tornado emergency issued in populated parts of oklahoma. this monster tomorrow even crisscrossing a busy highway. >> it makes its way closer and closer to i-35. >> reporter: warning viewers to take cover. >> you're in the path of the storm. you need to be going into your tornado shelter or the innermost room of your house immediately. >> reporter: in the wake, several homes destroyed. trees mangled. these cars at a standstill. so far two deaths have been reported. at least 20 million americans bracing tonight for severe

weather. more than 16 reported twisters today. and now new tornado watches in the louisiana and arkansas where winds up to 80 miles per hour tore through an airfield. in nebraska flooding and softball size hail shattering car windows. >> reporter: we're leaving tulsa and we heard there's another tornado warning. we've already seen two tornadoes touch down. it's been an active day. we're following the radar as well. we're going to keep driving to see what we can find. >> this series of storms following a weekend of wild weather. this monster twisting touching down near ray, colorado. this storm chaser getting uncomfortably close. >> we came out on the road, it was probably the most amazing tornado we've seen. >> reporter: watching the storm go from a thin streak to a quarter mile wide giant. >> we're always calculating

everything we're watching in front of us, teaching a close eye. there's 100 things going on all at once. >> look for a second. >> reporter: in that white car? another chase team. >> get right in there. >> reporter: trekking more than eight miles with 130 miles per hour winds. >> pictures. pictures. >> reporter: then it stops. a wall of wind and dirt spinning in place. debris somersaulting. it crosses the road. him saying he used the white clouds hundreds of feet up as a guide to stay safe. >> as long as we're outside of the wall cloud, there's no real risk outside of the bear cage. >> reporter: this, one of at least seven tornadoes in colorado over the weekend. the storms flattened homes, flipped trailers and tangled power lines in their wake.

>> it's not pretty. >> reporter: for some the perfect storm turned into the perfect selfie f. for this young couple, a prom photo they won't forget. >> reporter: for a lot, many of of them have shelters near their home. they can open them up and get under ground in a hurry. this one is especially large. you will see this one can hold as many as 25 people. once you're down inside you can see just how big it is. they have this equipped with flashlights and first aid kits so they can stay down here and ride out the storm. earlier as many people were boarding up, the storm chasers brett adair and brandon clemt were on the hunt for the big one. >> i have a dash cam up here that we run a live stream on. people can watch exactly what we're watching. >> reporter: their car outfitted with the highest tech for the perfect shot. risking it all for that

unbridled adventure. >> oh, my god. that was huge. >> reporter: in 2012 our ginger z road with a seasoned storm chaser. >> look at that. that was beautiful. on a four state 800 mile journey to study lightning. >> the problem is everyone is like it's easy. get in your car and go hear a rumble of thunder and park next to it and you're in. sometimes it's almost as difficult chasing a tornado as it is a good lightning storm. >> reporter: so we're going to go see it. >> armed with his high speed camera, he was attempting to document the birth of a lightning strike. >> there's 85 cameras on this taking the pictures. >> reporter: on this day he was joined by his son, paul. new to the team and eager to learn the family business. >> let's go. >> all right. >> reporter: it's happening. it's going to come right now. oh, my god.

as dusk settled in. >> cg. >> reporter: the moment they were waiting for, a classic thunderstorm bursting with lightning. and with paul on watch and tim manning the camera, they manage to snag a beautiful image. >> numerous branches. the first one hits the ground and the return stroke. >> oh, my god. >> reporter: the chase alone, reason enough to keep going. >> i don't know how many storms i've seen in my lifetime. but every single one of them, i still get pretty excited. the little boy in me wants to come out and watch and stare. >> reporter: it was that passion that took his life. in 2013 a deadly storm in oklahoma killed 18 people including tim, his son, paul, and their colleague, karl young. >> it's like a nightmare. >> reporter: this man new tim well. they worked together on the show "storm chasers". >> there's something that doesn't make sense. he knew exactly what he was

doing. he's always been controlled and safe. >> reporter: a reminder of how dangerous these storms can be. there were nearly 1200 tornadoes last year alone claiming 36 lives in the u.s. last year ginger visited this research lab at texas tech to learn how to survive a twister. >> we're locked and loaded. >> reporter: here a cannon simulates the power of a tornado. >> three, two, one. >> whoa. >> this missile will go through the standard residential structure. >> reporter: don't believe it? watch this. a 2 by 4 right through brick and cinder block. >> you don't want this going into you. if you have this wall, it won't. >> reporter: but some of the most critical moments can happen after a storm as ginger learned in texas. experts say it's important to not breathe. instead, immediately look around for anything that can be used as

a tool. >> wedge it underneath. you can see how much you can move that weight. you have a tool box that used to be your house. >> satellite funnels on the right. >> reporter: and tonight the region reeling from destruction as storm season barrels on ward. for "nightline," in tulsa, oklahoma. up next, we sit on a class to teach single women how to be a royal catch. call it marry harry. just on time for the prince's visit to america. and mouthwash. te but she's a dentist so...i kind of have to listen. she said "jen, go pro with crest pro-health advanced." advance to healthier gums... ...and stronger teeth from day one. using crest toothpaste and mouthwash makes my... ...whole mouth feel awesome. and my teeth are stronger too. crest-pro health advanced... ...is superior to colgate total... ...in these 5 areas dentists check. this check up? so good. go pro with crest pro-health advanced. mom's right...again!

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>> with prince harry in the states. . s millions of single american

women are hoping they might meet and marry the world's most eligible royal. one woman is running an etiquette school for want to be prin sa princess princesses. he's one of the world's most eligible bachelors, prince harry. >> reporter: and this week the prince himself will be state side in orlando, florida, for the invictus games. >> the privileges of being a prince gave me the extraordinary opportunity to help my military family. >> reporter: all this sending single women everywhere into full on marry harry mania, but if marrying the fifth in line of the british throne seems impossible, think again. >> do you think any of us american ladies have a chance? >> i do. he loves america. he's been open about that.

>> reporter: she can make your dreams come true. >> this is no joke. you think you're going to train the woman that ends up marrying harry? >> maybe i have. >> reporter: she runs an etiquette class called marry harry. teaching an aspiring princess. turns out there's a lot to learn. >> we never cross our legs at the knee. >> reporter: first up, the proper way to sit. kate middleton has perfected the slant. >> she does it all the tile. >> reporter: and once you're sitting, better mind your manners. >> it's really great. i want to shove the whole thing in my mouth. >> reporter: rule one, small bites. >> very small bites. >> reporter: okay. >> and the way you can test if

your bite was too big is if someone were to ask you a question right away, would you need to do the test. if you ever have to do that, the one minute moment, then it's a no, no. >> reporter: what if i need to excuse myself? >> take your napkin and pinch it in the middle. when you stand up, leave it in your chair. this signify if is that you're coming back. >> reporter: and use your napkin with discretion. >> you can dap in the middle. don't wipe. >> reporter: if you're out on the town, there's only one way to look lady like getting into a taxi. >> we're putting our backside in first, and then we keep knees and ankles together and it's swirl and pop, and then close. >> reporter: the course starts at 875. and it's extra if you want a facial so your skin is glowing in case you meet the prince. >> if this is what it feels like to be mrs. prince harry, i

recommend it. if it feels like a fairy tale, it may be because you've seen something like this before. anne hathaway taking a crash course from jewelry andrews in princess like posture. many women are hopeful this plot line can become their real life love story. prince harry is now 31 and a doting uncle. ever since his brother walked down the aisle, the world has been wondering who will prince harry end up with. >> is that who i think it is? >> that's prince harry. >> reporter: that question prompting none other than a reality show, i want to marry harry. in which a dozen women competed for the affections of what turned out to be a prince harry look alike. >> i'm not prince harry. >> reporter: as for the real harry? >> he has made no secret of the fact that he would really like to settle down one day and have

what his brother has. >> reporter: instead, he's thrown himself into his charity work. a soldier himself, prince harry actually founded the invictus game, a competition for wounded servicemen and women. he enlisted his grandmother, the queen to help the games. >> remember when you told us to bring it at the invictus games? >> careful what you wish for. >> boom. >> oh, really? >> reporter: as he told our robin roberts. >> how did you approach your grandmother? >> reporter: mrs. obama came to us with a challenge, and i didn't know what to do. she dragged her husband into it. happened to be the president. >> reporter: his american charm offensive will undoubtedly make him an even more desirable catch. >> do you think there will be very many ladies that go to orlando hoping they'll cross paths with the prince? >> i think there will be thousands of women going to

orlando to get the glimpse. >> reporter: meeting the prince, the first step in operation marry harry. >> coming up next, the real reason for harry's visit to america. one father, a wounded warrior is overcoming pain and disability to provide a moving life lesson for his son. ya know, viagra helps guys with erectile dysfunction get and keep an erection. talk to your doctor about viagra. ask your doctor if your heart is healthy enough for sex. do not take viagra if you take nitrates for chest pain or adempas® for pulmonary hypertension. your blood pressure could drop to an unsafe level. to avoid long-term injury, seek immediate medical help for an erection lasting more than four hours. stop taking viagra and call your doctor right away if you experience a sudden decrease or loss in vision or hearing. ask your doctor about viagra.

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>> finally tonight we mentioned that prince harry is in orlando. who is abc with the story of one father overcoming massive odds not only at the games but to provide something invaluable to his young son. >> the stories you're about to hear embody the true meaning of invictus. >> reporter: the games of competition for wounded service members shown on espn attract the likes of presidents, royals,

but it all comes town to the real stories of men and women like dt. air force master sergeants, isra israel dertooro was in gan. >> i was on fire from head to toe. i'm thinking i'm going to die here. i must have said it out loud. that's when the lieutenant said you're not going to die here. you said you will never let your son grow up without his dad. >> reporter: when he woke up, he was told he may never walk again. but he beat the odds. >> you learn to walk. you never think it would hurt so much. it was some of the most unbearable pain i can imagine that i went through. but i had to do it. i wanted to show my son, you know? dad went through a lot of crap, buddy, but he can still pull

out. when i saw myself for the first time, i was scared. and if i think i'm a monster, what's my three-year-old son going to think? >> when i saw the car pulling up to our driveway, i ran out. my mom said slow down. you're going to hurt him. i ran out the door, and my dad was all burned. i didn't really recognize him. >> all of a sudden he stops, and i'm like oh, crap. i was like is he scared of me. >> he was standing there, and i was like, papi, or just dad, and he was like, son, and i just gave him the greatest hug. >> dt continued to make his comeback. he was awarded the purple heart and then in 2010 he became the first 100% disabled veteran to reenlist in the air force.

and in 2014, he was able to compete in the inaugural invictus games in london. >> you're incredibly competitive. now you've taken a couple of records. >> the games here, i'm competitive, but they're not my big thing here. i'm more to educate. and to inspire. >> reporter: and now he is competing in his second invictus games. >> i beat the odds. unlike so many others, and it was only possible because i had hundreds of people who rallied around me and supported me. >> reporter: what is the definition to win to you? >> it wasn't have to be a medal. i can win at anything i do as long as i'm here. you're winning life. >> reporter: at the invictus games in orlando. >> amazing story. the invictus games air on espn